Cradle for marine railways.



J. L. CRANDALL.

CRADLE FUR MARINE RAILWAYS.

(Application filed June 25, 1901.)

(No Model.)

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N n b Witnesses: #Z LZ 3 Patented Ian. 7, I902.

UNITED STATES PATENT OFFICE.

JAMES L. CRANDALL, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO H. I.

CRANDALL 8a SON COMPANY, OF BOSTON, MASSACHUSETTS, A COR- PORATION OF MAINE.

CRADLE FOR MARINE RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 690,402, dated January '7, 1902.

Application filed June 25,1901. Serial No. 65,945. (No model.)

To all whmn it may concern:

Be it known that I, J AMES L. CRANDALL, of Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvementin Cradles for Marine Railways, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts. v

This invention relates to marine railways, sometimes called slipways or patentslips, and has for its object to construct a cradle especially adapted for a side-haul marine railway which can'be easily removed from beneath a ship after the ship has been hauled in and blocked up.

Heretofore so far as I am aware much (lifficulty has been experienced in removing the cradle after the ship has been hauled in and blocked up, as the ship has had to be first lifted free from the cradle; but with a cradle embodying this invention the ship is merely blocked up and then without lifting it from the cradle said cradle can be easily removed.

Figure 1 shows in side elevation a cradle for a marine railway embodying this invention. Fig. 2 is an end view of the cradle. Fig. 3 is a detail of a supplemental support which is movably mounted on top of the cradle and which constitutes the essential feature of my invention. of the supplemental support shown in Fig. 3. Fig. 6 is an enlarged view of a portion of the end of the cradle.

a represents a portion of the runway of an ordinary marine railway sufficient to illustrate my invention.

1) represents one of the inclined base-bars of the cradle, which, as herein shown, is composed of a number of bars or plates rigidly secured together to present a channeled basebar which receives within its channel a nu mber of rolls 1), which are journaled in suitable bearings provided for them, said rolls being arranged to run on the rails. There will be at least two of these inclined base-bars arranged in parallelism,and they are rigidly connected together by suitable connecting-bars.

A number of vertical bars 0 are erected on Figs. 4 and 5 are sectional details a rigid structure will be produced having inclined base-bars and horizontal top bars. So much of the cradle as above described may, however, be of any other suit-able construction. On top of the cradle thus formed a supplemental frame is mounted, which is movable relative to themain body portion of the cradle by sliding along within prescribed limits on the top portion thereof. The supplemental frame comprises, essentially, side bars 6, having rolls e beneath them which are held in place by suitable means, whereby said rolls 6 rest on and are free to move along on top of thehorizontal top bars d. The side bars 6 are arranged in parallelism with each other and are also arrangedin parallelism with the horizontal top bars d and are rigidly connected together to constitute a supplemental frame. As herein shown, the side bars ehave secured to their under sides at regular inter= vals bearing-plates e for the rolls 6 and also have secured to them. at each side opposite said bearing-plates supporting-plates e 6 which astride the horizontal top bars d, and said plates a e have elongated slots 6 for the journals of the rolls e. The supplemental frame thus provided is free to move along on the horizontal top bars of the cradle independently thereof, yet such movement is limited by the elongated slots 6 in the plates e e The cradle provided with the supplemental frame having been drawn under the ship and the cradle with the ship thereon having been hauled in, the ship will be blocked up in any usual or suitable manner, and then the pull upon the cradle is released, and when released said cradle will move back or retreat a short distance independently of and relative to the supplemental fralne,which remains at rest, and as the cradle thus moves down the inclined runway a short distance the supplemental frame gradually falls and leaves ICO the ship on the blocks. Thus it will be seen that the cradle is easily removed from be neath the ship without lifting the ship from the cradle.

I claim 1. In a marine railway, a cradle adapted to be hauled up the inclined runway having inclined base-bars, each provided with a number of rolls, horizontal top bars, and means for rigidly connecting all of said bars together to form a rigid structure, combined with a horizontal supplemental support movably mounted on said top bars which is adapted to receive upon it the ship, and means for limiting the independent movement of said support in opposite ways, substantially as de scribed.

JAMES L. ORANDALL.

Witnesses:

B. J. NoYEs, JOHN W. Dnonow. 

